| Popis: |
I. INTRODUCTION The cause of both the joys and sorrows of nitrite determination lies in its extreme reactivity. The joy is that it is readily reacted with a wide variety of compounds to form distinctive and unique derivatives that are easily measured. The form in which nitrite is most commonly determined, a diazo dye, is absolutely specific for nitrite, for no other compound will form diazo pigments. The sorrow is that because nitrite is so reactive, sample clean-up can become a very complex problem of removing compounds that compete for nitrite with the very reagents used to determine it. The substrates in which nitrite is most commonly determined are cured meats, which are collections of nitrite-reactive substances. The aim of sample preparation procedures for cured meats is to rid the system of nitrite reactants without losing nitrite in the process. Put in this manner, it would appear that the only critical part of the procedure is sample preparation, not the determination step. |
